Tear fluid cytokine levels may serve as biomarkers of innate immune system response against SARS-CoV-2 infection. Therefore, our aim was to analyze panel of selected inflammatory cytokines in tears of COVID-19 patients in relation to presence of SARS-CoV-2 viral load in conjunctival secretions. In this study concentrations of TNF-α, IL-1b, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12 p70, GM-CSF, and IFN-γ were determined by a magnetic bead assay in tear film collected from 232 symptomatic COVID-19 patients. SARS-CoV-2 ocular infection was confirmed based on positive conjunctival swab-based RT-PCR testing. Viral RNA in conjunctival sac was detected in 21 patients (9%). No relation between presence and the duration of ophthalmic symptoms and SARS-CoV-2 infection detected in conjunctival secretions was found. The tear film concentrations of IFN-γ, TNF-α, IL-5, IL-8 and GM-CSF were found to be significantly greater among patients with positive conjunctival swab results as compared to the group negative for SARS-CoV-2 in conjunctival sac. Our current data depict a group of inflammatory mediators in human tears, which may play a significant role in ocular pathology of SARS-CoV-2 conjunctival infection.

Diabetic retinopathy (DR) remains the leading cause of blindness in the working-age population. Its progression causes gradual damage to corneal nerves, resulting in decreased corneal sensitivity (CS) and disruption of anterior-eye-surface homeostasis, which is clinically manifested by increased ocular discomfort and dry eye disease (DED). This study included 52 DR patients and 52 sex- and age-matched controls. Ocular Surface Disease Index (OSDI) survey, tear film-related parameters, CS, and in vivo corneal confocal microscopy (IVCM) of the subbasal plexus were performed. Furthermore, all patients underwent tear sampling for neurotrophin and cytokine analysis. OSDI scores were greater in DR patients than in controls (p = 0.00020). No differences in the Schirmer test score, noninvasive tear film-break-up time (NIBUT), tear meniscus or interferometry values, bulbar redness, severity of blepharitis or meibomian gland loss were found. In the DR group, both the CS (p < 0.001), and the scotopic pupil diameter (p = 0.00008) decreased. IVCM revealed reduced corneal nerve parameters in DR patients. The stage of DR was positively correlated with the OSDI (Rs = +0.51, 95% CI: + 0.35–+0.64, p < 0.001) and negatively correlated with IVCM corneal nerve parameters and scotopic pupillometry (Rs = −0.26, 95% CI: −0.44–−0.06, p = 0.0097). We found negative correlations between the OSDI and IVCM corneal innervation parameters. The DR group showed lower tear film-brain-derived neurotrophic factor (BDNF) levels (p = 0.0001) and no differences in nerve growth factor (NGF)-β, neurotrophin (NT)-4, vascular endothelial growth factor (VEGF), interleukin (IL)-1β, IL-4, IL-5, IL-6, or IL-12 concentrations. Tumor necrosis factor (TNF)-α, IL-2, IL-8, IL-10, granulocyte macrophage colony-stimulating factor (GM-CSF), and interferon (IFN)-γ levels were decreased among patients with DR. Corneal innervation defects have a direct impact on patients’ subjective feelings. The evolution of DR appears to be associated with corneal nerve alterations, emphasizing the importance of IVCM.

Background/Objectives: Epiretinal membrane (ERM) is often associated with macular thickening and foveal intraretinal fluid. The aim of this study was to evaluate the efficacy of early postoperative SMLT (577 nm) in preventing persistent macular oedema and to assess its impact on selected functional and morphometric retinal parameters after ERM peeling. Methods: A total of 68 pseudophakic patients with ERMs were enrolled and randomly assigned (1:1) to a laser group or a nonlaser control group. SMLT was performed one month after PPV. The functional and morphometric retinal parameters were assessed preoperatively and at one and four months postoperatively via optical coherence tomography (OCT), OCT angiography (OCTA), multifocal electroretinography (mfERG), and microperimetry. Results: The reduction in total retinal volume between the first and fourth postoperative months was significantly greater in the SMLT group than in the control group (p = 0.02). No significant differences in functional parameters were found between the groups. A more substantial reduction in total retinal volume post-SMLT was associated with greater baseline macular thickness, a more advanced ERM stage, worse baseline visual acuity, greater fixation stability, lower initial macular sensitivity and lower preoperative p-wave amplitude in ring R1 on mfERG. Conclusions: SMLT may be considered a therapeutic option in patients with advanced ERM stages and low preoperative visual acuity.

Background/Objectives: Posterior vitreous detachment (PVD), which is closely related to epiretinal membrane (ERM) formation, can affect macular microstructure and function through persistent tractional forces. The aim of this study was to evaluate whether PVD status influences preoperative characteristics and long-term functional and morphological retinal outcomes after ERM surgery. Methods: Ninety patients who underwent idiopathic ERM removal were included and divided into two groups on the basis of intraoperative vitreous status: incomplete or complete PVD. Visual function, retinal imaging, microperimetry, and multifocal electroretinography (mfERG) data were assessed preoperatively and at 1, 4, and 12 months postoperatively. Results: At baseline, compared with the incomplete PVD group, the complete PVD group demonstrated greater fixation stability and lower variability, along with smaller foveal avascular zone (FAZ) areas in both superficial and deep vascular complexes. In terms of absolute postoperative values, the complete PVD group exhibited superior functional outcomes, including higher macular sensitivity and improved fixation variability parameters at 12 months. Morphologically, the incomplete PVD group showed consistently larger FAZ areas in both superficial and deep vascular complexes. In terms of changes from baseline, best-corrected visual acuity (BCVA) gain was greater in the complete PVD group at 1 and 4 months, with no difference at 12 months, whereas no significant between-group differences were observed for other functional or morphological parameters at any time point. Conclusions: Complete PVD is associated with faster visual recovery. Incomplete PVD may induce alterations at the retinal microcirculation level that persist postoperatively and influence microperimetric scores.